DataBasePath:=System.IOutils.TPath.GetDocumentsPath

  DBFileName:=System.IOutils.TPath.Combine(System.IOutils.TPath.GetDocumentsPath,'Storage.fdb');
  if not System.IOutils.TFile.Exists(DBFileName) then
    ShowMessage('нету как-то файлика');

  uses
  System.SysUtils, 
  System.Types, 
  System.UITypes, 
  System.Classes, 
  System.Variants,
  FMX.Types, 
  FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, FMX.TabControl,
  System.Rtti, FMX.Layouts, FMX.Grid, FMX.Objects,
  System.IOutils, FMX.Controls.Presentation, FMX.StdCtrls, FMX.Effects, FMX.Edit,
  FMX.ListBox, 
  FMX.Ani,

  Data.DB,
  FireDAC.Phys.FB,
  FireDAC.Comp.Client,
  FireDAC.Stan.Intf,
  FireDAC.Stan.Option,
  FireDAC.Stan.Error,
  FireDAC.Phys.Intf,
  FireDAC.Stan.Def,
  FireDAC.Stan.Pool,
  FireDAC.Stan.Async,
  FireDAC.Phys,
  FireDAC.Phys.FBDef,
  FireDAC.UI.Intf;

FDpdl:TFDPhysFBDriverLink; //глобальная

procedure TfmMain.Button1Click(Sender: TObject);
var
  DBFileName:string;
begin
  FDpdl:=TFDPhysFBDriverLink.Create(Self);
  FDpdl.VendorLib:=ExtractFilePath(ParamStr(0))+'libfbembed.so';
  Text11.Text:=FDpdl.VendorLib;
  FDConnection1.DriverName:='FB';
  FDConnection1.Params.DriverID:='FB';
  DBFileName:=System.IOutils.TPath.Combine(System.IOutils.TPath.GetDocumentsPath,'Storage.fdb');
  FDConnection1.Params.Values['Database']:=DBFileName;
  FDConnection1.Params.Values['User_name']:='SYSDBA';
  FDConnection1.Params.Values['Password']:='masterkey';
  FDConnection1.Connected:=True;
end;